/*
    Copyright (C) 2014-2019 de4dot@gmail.com

    This file is part of dnSpy

    dnSpy is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    dnSpy is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with dnSpy.  If not, see <http://www.gnu.org/licenses/>.
*/

using System;
using System.Diagnostics;
using dnSpy.Contracts.Decompiler;

namespace dnSpy.Documents.Tabs.DocViewer {
	sealed class LazyBlockStructureCollection {
		public static readonly LazyBlockStructureCollection Empty = new LazyBlockStructureCollection();

		public BlockStructureCollection Collection {
			get {
				if (coll is null) {
					Debug2.Assert(ranges is not null);
					coll = new BlockStructureCollection(ranges);
					ranges = null;
				}
				return coll;
			}
		}
		BlockStructureCollection? coll;
		CodeBracesRange[]? ranges;

		LazyBlockStructureCollection() => coll = BlockStructureCollection.Empty;

		public LazyBlockStructureCollection(CodeBracesRange[] ranges) => this.ranges = ranges ?? throw new ArgumentNullException(nameof(ranges));
	}
}
